A standard easy-open package comprises a vessel having a flat rim and a profiled or planar cover foil that is bonded to the vessel at the rim. The vessel and foil together form one or more compartments that can contain respective foodstuffs, although it is of course within the scope of this invention for other types of materials to be thus packaged. As described in German utility model 6,901,362 the cover foil is unitarily formed with an open or tearoff tab that projects laterally out past the rim of the vessel. Furthermore the metal of the cover foil is formed with a tear line that extends around the compartment, just within the inner edge of its periphery, and that runs out on each side of the tearoff tab. Thus the user can lift the tearoff tab, separating the metal layer here from the rest of the foil by breaking the bond between the vessel and the tearoff tab and then tearing the plastic layer at the lines flanking it so as to pull it free from the rim and tear out the center of the foil to expose the contents of the compartment, normally leaving the plastic layer of the tab at least still sticking to the rim.
Both the vessel and the foil can be made of a metal, of a synthetic-resin, or of a laminate of both. A particularly advantageous system has a rigid vessel to which is bonded a polypropylene-coated metallic foil, the bonding being done ultrasonically along bond lines running around the perimeters of the compartments, although a cold or adhesive bond is also within the scope of this invention. Similarly in German patent document No. 3,613,155 the vessel is formed of such a metal/plastic laminate that itself is formed with the tear line so that when the foil is stripped it takes part of the rim of the vessel with it.
Such systems provide a durable and hermetic seal, but normally require considerable force to open.